Cerberus
It depends on a number of factors. We were looking at doing it on the May long weekend because there were a number of my family and friends that would be coming out from BC. This would give them an extra day paid to get to/from the wedding.
For me, I agree with the several posts that it's the bride and grooms day. If this is considered a dick move, then perhaps they're not the friends you thought they were, and vice versa.
DrTyore
I find it interesting...
Many people are bringing up the "Well, if they're upset, they're not really your friends" argument. I get upset with my friends all the time, as I'm sure they do me. It doesn't change the fact that I love the bastards, but I 100% guarantee there are long weekend plans they'd prefer over a wedding. I don't mean they aren't going to come, or are going to hate you for it, but they'd love to attend MORE on a non long weekend date.
I agree with Cerebrus there with the far travelling family, it's more understandable, but still less than ideal.
The second argument of "It's my day, so..." is also weak. everyone wants the perfect wedding of course! But let me give you an example from a wedding I was best man in a few years ago. The fella didn't hire a DJ, figuring he can just get an iPod and load up a song set. No problem then, he said he'll put together the song list, we'll compile and set it up. I get to his house, and every single song is by Bob Dylan, Leonard Cohen, Johnny Cash, and their like. Now, this is a great set of songs for me to sit with a few beers to, but NOBODY is going to enjoy that wedding. No songs to dance to, obscure songs half the people won't know, and some are downright depressing (seriously, even LC says "Hallelujah" is ready for retirement). I told the groom he can pick 5 to hear through the night, and I veto'd any that were not wedding appropriate. Should I have just said "Well, it's your day"?
Mark